ldiskfs/kernel_patches/patches/linux-5.4/ext4-hash-indexed-dir-dotdot-update.patch

   1 From eb2cc3a5d4cfb8feee399507a8f2e2fe17f96cf4 Mon Sep 17 00:00:00 2001
   2 From: Shaun Tancheff <stancheff@cray.com>
   3 Date: Tue, 6 Aug 2019 18:12:53 -0500
   4 Subject: [PATCH] + linux-5.3/ext4-hash-indexed-dir-dotdot-update.patch
   5
   6 ---
   7  fs/ext4/namei.c | 71 +++++++++++++++++++++++++++++++++++++++++++++++++
   8  1 file changed, 71 insertions(+)
   9
  10 diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
  11 index f54e868..14ff68e 100644
  12 --- a/fs/ext4/namei.c
  13 +++ b/fs/ext4/namei.c
  14 @@ -2174,6 +2174,74 @@ out_frames:
  15         return retval;
  16  }
  17
  18 +/* update ".." for hash-indexed directory, split the item "." if necessary */
  19 +static int ext4_update_dotdot(handle_t *handle, struct dentry *dentry,
  20 +                             struct inode *inode)
  21 +{
  22 +       struct inode *dir = dentry->d_parent->d_inode;
  23 +       struct buffer_head *dir_block;
  24 +       struct ext4_dir_entry_2 *de;
  25 +       int len, journal = 0, err = 0;
  26 +
  27 +       if (IS_ERR(handle))
  28 +               return PTR_ERR(handle);
  29 +
  30 +       if (IS_DIRSYNC(dir))
  31 +               handle->h_sync = 1;
  32 +
  33 +       dir_block = ext4_bread(handle, dir, 0, 0);
  34 +       if (IS_ERR(dir_block)) {
  35 +               err = PTR_ERR(dir_block);
  36 +               goto out;
  37 +       }
  38 +
  39 +       de = (struct ext4_dir_entry_2 *)dir_block->b_data;
  40 +       /* the first item must be "." */
  41 +       assert(de->name_len == 1 && de->name[0] == '.');
  42 +       len = le16_to_cpu(de->rec_len);
  43 +       assert(len >= EXT4_DIR_REC_LEN(1));
  44 +       if (len > EXT4_DIR_REC_LEN(1)) {
  45 +               BUFFER_TRACE(dir_block, "get_write_access");
  46 +               err = ext4_journal_get_write_access(handle, dir_block);
  47 +               if (err)
  48 +                       goto out_journal;
  49 +
  50 +               journal = 1;
  51 +               de->rec_len = cpu_to_le16(EXT4_DIR_REC_LEN(1));
  52 +       }
  53 +
  54 +       len -= EXT4_DIR_REC_LEN(1);
  55 +       assert(len == 0 || len >= EXT4_DIR_REC_LEN(2));
  56 +       de = (struct ext4_dir_entry_2 *)
  57 +                       ((char *) de + le16_to_cpu(de->rec_len));
  58 +       if (!journal) {
  59 +               BUFFER_TRACE(dir_block, "get_write_access");
  60 +               err = ext4_journal_get_write_access(handle, dir_block);
  61 +               if (err)
  62 +                       goto out_journal;
  63 +       }
  64 +
  65 +       de->inode = cpu_to_le32(inode->i_ino);
  66 +       if (len > 0)
  67 +               de->rec_len = cpu_to_le16(len);
  68 +       else
  69 +               assert(le16_to_cpu(de->rec_len) >= EXT4_DIR_REC_LEN(2));
  70 +       de->name_len = 2;
  71 +       strcpy(de->name, "..");
  72 +       ext4_set_de_type(dir->i_sb, de, S_IFDIR);
  73 +
  74 +out_journal:
  75 +       if (journal) {
  76 +               BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
  77 +               err = ext4_handle_dirty_dirblock(handle, dir, dir_block);
  78 +               ext4_mark_inode_dirty(handle, dir);
  79 +       }
  80 +       brelse(dir_block);
  81 +
  82 +out:
  83 +       return err;
  84 +}
  85 +
  86  /*
  87   *     ext4_add_entry()
  88   *
  89 @@ -2229,6 +2297,9 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
  90         }
  91
  92         if (is_dx(dir)) {
  93 +               if (dentry->d_name.len == 2 &&
  94 +                   memcmp(dentry->d_name.name, "..", 2) == 0)
  95 +                       return ext4_update_dotdot(handle, dentry, inode);
  96                 retval = ext4_dx_add_entry(handle, &fname, dir, inode);
  97                 if (!retval || (retval != ERR_BAD_DX_DIR))
  98                         goto out;
  99 --
 100 2.20.1
 101